1. Field of the Invention
The present invention relates generally to ratchet conveyors, and particularly to ratchet conveyors that provide for movement in two directions.
2. Background of the Invention
Ratchet conveyors are known in the art and typically include a rigid central carrier bar operated in a back and forth motion by a hydraulic cylinder. The bar includes a plurality of gravity actuated dogs pivotally secured thereto for contacting and pushing objects such as carts, and the like. Thus, when the cylinder is extended, the dogs push against the surface of the object, moving it the length of the extending stroke of the cylinder. Conversely, when the cylinder retracts, the dog is designed to pivot downwardly underneath the object and then rotate to an up or contacting position when no longer blocked by the object. Therefore, subsequent re-extension of the cylinder provides for movement of the same or a further object. In this manner, articles are moved in a ratcheting or start and stop type motion from one end of the conveyor to the other.
Ratchet conveyors have various advantages, such as mechanical simplicity, durability and the ability to lie closely parallel each other, as a result of the cylinder drive means being located centrally thereof.
However, unlike continuous motor driven chain conveyors, which can include means for reversing motor direction and therefor chain movement, ratchet conveyors can only move a product in one predetermined direction depending on the way in which the dogs are mounted to the central bar. Accordingly, it would be desirable to have a ratchet conveyor that can provide for ratchet movement of products along the length thereof in either direction.